<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        div {
            /* 下划线 */
            text-decoration: underline;
        }
        p {
            /* 删除线 */
            text-decoration: line-through;
        }
        h2 {
            /* 上划线 */
            text-decoration: overline; 
        }
        a {
            /* 无装饰线 */
            text-decoration: none;
        }

    </style>
</head>
<body>
    <div>div</div>
    <p>ppp</p>
    <h2>h2</h2>
    <a href="#">我是超链接</a>
    
</body>
</html>